Supervised Learning Flashcards

(28 cards)

1
Q

Example Scenario: Email Spam Detection

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2
Q

Consider an email service provider implementing a spam detection system. The goal is to

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3
Q

emails as either “spam” or “not spam” (also known as “ham”).

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4
Q

Precision:

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5
Q

Precision measures the proportion of corectly identified spam emails out of all emails

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6
Q

by the model.

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7
Q

Formula: Precision = True Positives / (True Positives + False Positives)

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8
Q

True Positives (TP): The number of emails correctly classified as spam.

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9
Q

False Positives (FP): The number of non-spam emails incorrectly classified as

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10
Q

Precision Example: Let’s say the spam detection system flagged 100 emails as Sp

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11
Q

inspection

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90 of them were actually spam (True Positives)

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12
Q

Precision = 90 /(90 + 10) = 90%

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13
Q

So

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in this scenario

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14
Q

flagged as spam

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90% of them were actually spam

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15
Q

Recall:

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16
Q

Recall measures the proportion of correctly identified spam emails out of all actual

17
Q

dataset.

18
Q

Formula: Recall =True Positives / (True Positives + False Negatives)

19
Q

False Negatives (FN): The number of spam emails incorrectly classified as no

20
Q

Recall Example: Suppose there were I 50 actual spam emails in the dataset. The spa

21
Q

correctly identified 90 of them as spam (True Positives)

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but it missed 60 spam emails

22
Q

Recall = 90/(90 + 60) = 60%

23
Q

In this case. the recall ofthe spam detection system is 60%. This indicates that out of all

24
Q

the system managed to identify 60% of them correctly

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but it missed 40%.

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Interpretation:
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• High Precision: Indicates that when the model preuicts an email as spam
it 19
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correct. This reduces the chances of legitimate emails being incorrectly marke
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crucial for user trust and satisfaction